The present invention is related to the field of control systems, and, more particularly, to a control system for a vehicle and associated methods.
Vehicle security systems are widely used to deter vehicle theft, prevent theft of valuables from a vehicle, deter vandalism, and to protect vehicle owners and occupants. A typical automobile security system, for example, includes a central processor or controller connected to a plurality of vehicle sensors. The sensors, for example, may detect opening of the trunk, hood, doors, windows, and also movement of the vehicle or within the vehicle. Ultrasonic and microwave motion detectors, vibration sensors, sound discriminators, differential pressure sensors, and switches may be used as sensors. In addition, radar sensors may be used to monitor the area proximate the vehicle.
The controller typically operates to give an alarm indication in the event of triggering of a vehicle sensor. The alarm indication may typically be a flashing of the lights and/or the sounding of the vehicle horn or a siren. In addition, the vehicle fuel supply and/or ignition power may be selectively disabled based upon an alarm condition.
A typical security system also includes a receiver associated with the controller that cooperates with one or more remote transmitters typically carried by the user as disclosed, for example, in U.S. Pat. No. 4,383,242 to Sassover et al. The remote transmitter may be used to arm and disarm the vehicle security system or provide other remote control features from a predetermined range away from the vehicle.
As disclosed in U.S. Pat. No. 5,049,867 to Stouffer and Pat. No. 5,146,215 to Drori, the security system controller may include features to store and compare unique codes associated with a plurality of remote transmitters, each remote transmitter having its own unique code initially programmed therein. U.S. Pat. No. 5,146,215 in particular discloses that remote transmitter codes may be added or deleted from the controller corresponding to the number of remote transmitters desired by the user.
Other vehicle security systems include a passive transponder, typically carried on the key ring of the user. The transponder must be presented within the vehicle to an associated transponder reader to permit the vehicle engine to start and run. The transponder includes a transmitter and a receiver. The receiver is used to capture energy radiated from the transponder reader. This energy is temporarily stored and used to power the transmitter.
There are also other desirable features of many conventional vehicle security systems, such as the ability to place the system in a valet mode so that others may use the vehicle without triggering the alarm. Typically a valet switch is positioned so as to be hidden in an area not readily visible in the vehicle. The user may operate the valet switch to enter the valet mode and exit the valet mode. In addition, the valet switch also has been used to permit the user to stop an alarm, such as when the user loses a remote transmitter or the battery fails, for example. The hidden valet switch may be awkward to operate and may also be of limited security value, since there are only so many places to position such an important switch within the vehicle.
U.S. Pat. No. 5,467,070 to Drori et al. discloses a vehicle security system including a valet switch in the form of a three-position slide switch which includes an open center position, a momentary contact side position, and a latched side position. To enter a code digit, the user taps and releases the momentary side of the valet switch the number of times corresponding to the digit to be entered followed by a motion to the latched side to signal completion of the digit. If the code has multiple digits, the process is repeated for each digit. When a correct valid code is entered, the siren is chirped a predetermined number of times to indicate that a valid code has been entered.
Unfortunately, the three-position slide switch may be difficult to operate. Since the switch may also be positioned out of view of the driver, the three positions may be awkward to coordinate. In addition, confirmation of the entry of the correct digit may permit a would-be thief to try a number of code permutations and thereby determine the correct code.
In view of the foregoing background, it is therefore an object of the present invention to provide a vehicle control system that is readily entered into a desired mode, yet which provides high security for the user.
This and other objects, features, and advantages in accordance with the present invention are provided by a vehicle control system comprising a controller vehicle for performing at least one vehicle function responsive to a transmitter, the controller being switchable among a plurality of modes; and a switch at the vehicle and cooperating with the controller for switching the controller to a desired mode responsive to operation of the momentary contact switch in a sequence corresponding to a multi-digit user code.
The controller preferably counts operations of the switch, such as a momentary contact switch, occurring within a predetermined time of each other as a respective digit of the multi-digit user code. In addition, the controller, within a predetermined time window after a previous operation, may count successive operations of the momentary contact switch within a predetermined time of each other as a next digit of the multi-digit user code. Accordingly, the user can readily enter his multi-digit user code, while a would-be thief would be unable to try all of the possible multi-digit code permutations. User convenience is enhanced without compromising security.
The controller may be switchable to a transmitter learning mode for learning at least one new uniquely coded transmitter. The controller may also be switchable to a valet mode, coded override or off mode, or a feature programming mode, for example. Of course, the controller also typically has one or more normal operating modes, such as armed and disarmed modes.
The multi-digit user code preferably comprises a two digit code. In addition, each digit of the multi-digit user code is preferably between one and nine. An indicator may be provided for confirming entry of a digit of the multi-digit user code. Such an indicator preferably does not indicate entry of the correct digit, but rather just entry of a digit so that the user knows to then enter the second digit. Moreover, a would-be thief is not quickly notified that a correct digit has been entered.
A method aspect of the invention is for switching a controller at a vehicle among a plurality of modes. The controller is preferably for performing at least one vehicle function responsive to a transmitter signal. The method preferably comprises the steps of: providing a depressable switch at the vehicle and connected to the controller, and depressing the switch in a sequence corresponding to a multi-digit user code and switching to a predetermined mode responsive thereto. The method also preferably includes the step of using the controller to count operations of the switch occurring within a predetermined time of each other as a respective digit of the multi-digit user code.
The method may also include the step of, within a predetermined time window after a previous operation, using the controller to count successive operations of the switch within a predetermined time of each other as a next digit of the multi-digit user code. As mentioned above, the predetermined mode may be at least one of a transmitter learning mode, a valet mode, a coded override mode, and a feature programming mode.